The Universalist. [volume] (Chicago [Ill.]) 1884-1897, 1887-01-22
THE SCIENCE OF SLEEP.

Each successive graduation in sleep is
marked by the inclusion of nervous
system, which is for the time being shut
off, SO to speak, from participating in the
general life functions of the individual
until, when the maximum intensity is
obtained, nothing is left but the purely
animai-one might almost say the vegeta-
tive-life. Sleep of this degree of inten-
sity, although perfectly normal process,
is not, in health, Of long duration. After
the lapse of variable space of time the
systems one by one resume their func-
tons, until finally the sum OF percep-
tions bring about the condition OF
awakening.
The brain shares in the need, which is
everywhere apparent, of periods of rest.
The products of cerebral activity accu-
mulate more rapidly than they are elimin-
ated, and period, therefore, arrives when
the tissues are no longer able to do their
work. The result is an invincible feeling
OF indisposition to exertion, physical or
mental. The temporary and involuntary
cessation of activity is at once followed
by diminution OF the blood supply; the
an@mis SO induced being, therefore, q
consequence, and not cause, of the state
OF repose.
The various parts of the nervous sys-
tenn are not all involved simultaneously
or to the same extent. The centres gov
erning voluntary movement are the first
to be affected, as seen in the nodding of
the head and the closure OF the eye-lids
and the body, if not prevented, tends to
assume the position of repose determined
by the laws of gravity. The special
senses soon follow, but here again they
are not abrogated en- nadsse. Sight is the
first to CO. the Stimulus no longer reach
ing that position of the cerebrum where
it can give rise to definite sensation.
even where the closure of the lids has
not shut off the external stimuli alto
| gether. Hearing and smell are remark
ably persistent, and except in the deepest
sleep, may be said to be only dulled and
not extinguished. Every one is familiar
with the ease with which sleep is put TO
an end by unaccustomed noise, even of
slight intensity, or, better still, by the
cessation of any monotonous sound, as
for instance the awakening of travellers
by rail or steamboat on any stoppage OF
the train or machinery. Instances are
| ~, kon H. sx.l LII -
house have been reused simply by the
smell of tobacco INDUCED in by mex
perienced or incautious burglars. The
persistent sensibility of the senses may
to some extent, be accounted for by the
fact that they we're not cut off from COM
munication with the outside world as are,
for example, the eyes. To allow sleep, or
at any rate quiet sleep, certain harmony
must exist in the condition of all the
organs, which must, SO to speak, be tuned
to the sleep tune. If one organ be in d
state of activity, or, on the other hand,
its condition be abnormal in some other
way, the sensorium refuses to abdicate
its control. This is familiar to us in the
case of cerebral activity or cold feet at
bedtime, both being inimical to Sleep
Inasmuch, therefore, insomnia may result
from either set of causes, we can either
employ drugs, such as opium, which act
directly on the nerve centres and bring
about sleep, or we may resort to medicines
like hypnotic, which is said to favor sleep
rather than induce, by allaying the irrita-
BILE or hyperesthetic condition of certain
organs or parts. = British Medical
Journal.